is black the color of no color?

[Mapidus]

There's a very interesting philosophical question related to the posts here:
Should color be classified as a primary quality or a secondary quality under John Lockes duality system. When Locke formulated his system, he classified color as a secondary quality. Basically this meant that he believed that color was not an inherent and accurate attribute that can be measured independent of observers. A primary quality would be one like length. Some mention color as being the property of the object to absorb certain wavelengths and reflect certain others. These definitely seem like primary attributes and would allow us to classify color as a primary quality. But then some consider color to be what they observe, pulpp stated about how she "see" black when she closes her eyes. This would lead to a classification of color as a secondary quality that is dependent on observation.

So, I think part of the conflict in what people believe here is that some consider color a primary quality and some a secondary quality. So this gives us an interesting question: Is a can of Coke red when there is no light?

 

[amdforlife]

whops...kept reading "color" and it snuck in there. you keep talking about "humans"...i dont see how any animal could see black, if it has no light. and if a black object is visible to anything...then its either not perfectly black, or not perfectly smooth.

 

[Jothaxe]

[/i] >>

Argh... [/i] >>



Hehe Elledan

Just when you think the thread is all wrapped up...

-jothaxe

p.s. Although its all still somewhat theoretical black holes do emit Hawking Raditation, which has some wavelength regardless of the fact that its probably not in the visible spectrum. This means that nothing[i/] perfectly absorbs all electromagnetic radiation, so there is no such thing as "black" in this sense. But of course it depends on how you define black... which is why I continue to claim this is a philosophical question.

 

[Jothaxe]

<< Is a can of Coke red when there is no light? >>



My philosophical answer to a good philosophical question:

Yes it is red in the sense that the pigment on the surface of the coke can still reflects red light, regardless of whether there are any photons incident on the surface of the can at any given time. I argue that its not the act of reflecting red that makes the can red, but the ability of the can to reflect red that makes it red.

-jothaxe

 

[amdforlife]

<< Is a can of Coke red when there is no light? >>

no. because the coke can is a filter. it takes in light, and filters out ever color besides red...which is why we see the red. therefore, if theres no light to filter, there can be no color seen, which means you cant see red.
this question is just like if a tree falls in a forest, and no one is around does it still make a sound.

 

[Elledan]

<< you keep talking about &quot;humans&quot;...i dont see how any animal could see black, if it has no light. and if a black object is visible to anything...then its either not perfectly black, or not perfectly smooth. >>

It's very simple. Each animal (including Humans) can only see in a limited part of the EM spectrum (wavelengths), if an object absorbs all of the wavelengths in the visible spectrum of an animal, this animal will notice the absence of light, i.e. black. An animal which is able to see shorter wavelengths (say infrared) can see the object because this object doesn't absorb shorter wavelengths than those in the visible spectrum of the first animal. That's why bees see the world different from us Humans, their visible spectrum lies higher (i.e. in the higher wavelengths), so what we see as black can have any color to them. The same counts for all other ojects. Some colors can't even be seen by bees, so an object which only returns any of those colors is black to a bee.

 

[amdforlife]

ok i think i see what you're saying...so if i took a bee into a room with me, with this coke can, and cut out all possible sources of light, it is possible for the bee to still see the can?

 

[Jothaxe]

<<

<< Is a can of Coke red when there is no light? >>

no. because the coke can is a filter. it takes in light, and filters out ever color besides red...which is why we see the red. therefore, if theres no light to filter, there can be no color seen, which means you cant see red.
this question is just like if a tree falls in a forest, and no one is around does it still make a sound. >>



amdforlife: Let me see how this arguement holds up under &quot;magnification.&quot;

By your reasoning, the can is red only when it reflects red light. What if only a single photon (of the appropriate red wavelength) hits the can inside of a say, a second. Does this mean that the can is only red during the portion of this second while the photon is incident? This is sketchy at best, because quantum mechanically speaking, we cant be entirely certain of where the photon is, and where its heading in any given moment. But if we dont know both of these things, we can only say with a certain probability when the photon is even incident.

Conclusion: your definition implicitly calls for &quot;probabilistic color&quot; so I dismiss it.

-jothaxe

 

[amdforlife]

assuming that the photon revealed the whole can, then for that single second... we can be sure its red. when the photon leaves, the can is black again. you cant run a marathon if you have no feet, and the can cant be red if there is no light.

 

[Amused]

<< I think:

Black= all colours
White= the absence of colour >>



Sorry, but you're completely backwards.

Black: Absence of all color
White: All colors

 

[Elledan]

<< ok i think i see what you're saying...so if i took a bee into a room with me, with this coke can, and cut out all possible sources of light, it is possible for the bee to still see the can? >>

If you mean with light all wavelenghts in the visible spectrum of Humans, yes. Bees can see infrared, so if there's a source which emits infrared, the bee will see the can and you will not

 

[Jothaxe]

<< assuming that the photon revealed the whole can, then for that single second... we can be sure its red. when the photon leaves, the can is black again. you cant run a marathon if you have no feet, and the can cant be red if there is no light. >>



No offense, but I believe that you entirely missed my point. I am not saying that the photon hits the can for a full second. I am saying that we know that it hits sometime within the second. The actual time it takes to reflect would be infinitesimal.

So this means that since we can never know when the photon actually &quot;hit&quot; the can, the best we can do is smear the probability across time and have &quot;probabilistic color.&quot; Since this concept is unecessarily complicated, I feel its best we throw out the definition that brings it about.

-jothaxe

*edit for spelling*

 

[RossGr]

In the portion of the Electro-Magnetic spectrum which we refer to as visible light, roughly 380nm ?780nm, all colors of the rainbow Red, Orange, Yellow, Green, Blue, Indigo, Violet, can be assigned specific wave length values. Black and white do not share this property there is no wave length associated with those ?colors?. Black and White are more physiological then physical. Our EYE/Brain interprets the reception of all, or even a fair representative (RGB) of the spectrum as white, likewise our EYE/Brain interprets a lack of light as black. This seems to be the root of many troubles here, some are speaking of the physical nature of light and others the physiological nature of our perception of light, you need to consider both aspects to get the correct answer.

Hope this helps.

 

[XCLAN]

Black= all colours............really doe

 

[Noriaki]

<< assuming that the photon revealed the whole can, then for that single second... we can be sure its red. when the photon leaves, the can is black again. you cant run a marathon if you have no feet, and the can cant be red if there is no light. >>

The coke can isn't anything but an object. That object reflects EM radiation near the low end of what the human eye can detect. If there is no EM radiation hitting that coke can it has nothing to reflect.

The question of is the coke can black in a dark room is irrelevant.

If you blocked the part of the (visible) EM spectrum that is red but left the rest in tact (again visible) the coke can would be black.

Don't believe me? Take a white shirt, go into a dark room and shine a green light on it. The shirt is now green.

That white object would reflect enough of the EM spectrum for a human to percieve it as white, but there isn't enough of the EM spectrum coming in contact with it, there is only the green portion. But that object does reflect the EM wavelength we associate with green which is available thus the human eye percieves it as green.

(Note: This would have to be a perfectly green light, no traces of red or blue or yellow or purple or anything else, you can observe the effect to some degree with a mostly green light, though it won't be perfect).

You question about is the Coke can red in a dark room is really scientifically irrelevant. That dark room can not reasonably be completely free of EM radiation. Free of all radiation our very limited radiation detectors (aka eyes) can detect, but certainly not free of the whole spectrum.
There is no radiation in the &quot;visible light&quot; part of the spectrum there for that can to reflect thus the human eye precieves this lack of EM relfection as black.
Depending on what parts of the EM spectrum are in that room and what the can is reflecting and absorbing some other radiation detector will be able to &quot;see&quot; the can (whether that radiation detector is on another living creature or a man-made one).
All along the EM spectrum the coke can absorbs some wavelengths and reflects others. The fact that we are blocking the small part called visible light is really scientifically irrelevant, the coke can continues to block some wavelengths and absorb others. You've really changed very little.


Conclusion:
The physical properties of the can do not change in the absence of humanly visible EM Radiation, but our perception of it does.

If that makes it black or not, is a philisophical question.
But from a purely scientific point of view it's irrelevant.

Again, I don't think philosophy is useless or anything of the sort, I'm just not a philosopher myself, I have a very scientific mind, I have trouble getting past the fact that it's irrelevant to ponder the black/red red question in a human-perception context.
And interesting question though


The same can be said for the tree in the forest. I don't understand sound quite as well as I do optics becuase I don't like it as much and haven't studied it, but the basic premise of sound is that it is simply vibrations traveling through some sort of matter (liquid, solid, gas...doesn't really matter). &quot;Sound&quot; is simply the human interpretation of those vibrations (again it has to be a certain range, in this case I believe it's roughly 20-20,000 vibrations per second (Hz) for the average huamn, human's can't &quot;hear&quot; all vibrations, however a dog for example can &quot;hear&quot; higher than 20,000Hz, that's why a human can't hear a Dog Whistle).
The tree falling in the forest still vibrates molecules around it, thus producing the scientific requirements for &quot;sound&quot;. There is no human around to percieve it as a sound....is it still a sound? Again to me an irrelevent question, you'll have to ask a philosopher.

 

[Mapidus]

Noriaki: The question is not scientifically irrelevant. I posed it to see if people treat color as a primary or secondary quality. Primary qualities of objects are what allows science in the first place (things such as mass, length, and extension). A Coke can, even if nobody ever sees it, still has its specific reflection distribution fuction that gives it the perceived color when some quantity of EM is incident on it. Some people call this the color of the can and it is a primary quality. Other people consider color what they see, which is dependent on environment and observer, so this would classify color for these people as a secondary quality. Lets pose this other question then: Given two people, one has standard distribution S,M, and L color cones in their eyes. Another person has only S and L cones (colorblindness essentially). If you ask each person what color the coke can is, you might get different answers. So does the Coke can really have two different colors? Well it depends on how you define color (either as an inherent physical attribute (the reflection distribution function) or as a perceived thing or as both. I think what Jothaxe is trying to say is that the coke can has a reflection distribution function that is independent of perception, so this should be considered the color quality of objects since it is biased by observation. Amdforlife on the otherhand prescribe to the notion of color as a perceptual thing, which definitely is affected by environment and observer. I think both ways of thinking are fine and consider an object to have a &quot;true&quot; color and a &quot;perceived&quot; color. Science should try to work with the &quot;true&quot; color or else based on false premises, you can get to false conclusions. The exception to this of course would be perception related sciences which are not always exact such as psychology and color science since learning about the weaknesses and variance of perception is very important here.

 

[konichiwa]

Sorry to take this (way) off topic, but I have to address this:

<< Yeah, like some guy that can't even talk knows everything about the universe. >>

I work with people like Stephen Hawking every day -- as a matter of fact, my company sold Stephen Hawking his machine that talks. Just thought I'd lay that down initially to make sure we both understand that I have quite a bit more knowledge (and experience) than you do. And, as opposed to logically arguing against the ignorant statement you just made, I thought I'd share with you something that one of my clients who is unable to talk has written on his computer monitor:

Just because I cannot speak does not mean I have nothing to say.

I'd hope that in the future you can realize how lucky you are that you are able to walk, talk, jump, run and do everything else that you take for granted. And I also hope that you'll realize that if something tragic ever happens to you and you are unable to talk, that does not mean you have nothing to say.

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